I'm getting pleanty of funky knock out of my engine. Wondering if perhaps I colapsed a couple lifters or if they are possibly bottoming out.

I installed new springs which are MUCH stiffer than stock but kept the stock lifters. To be specific they are comp cams 987 springs with a seat pressure of around 120 lbs and something like 300 lb/in spring.

Anybody else out there running stock lifters w/ aftermarket springs? Thanks for the help!!